selective laser sintering process - Understanding SLS models

The basic material consists of powder with particle sizes of around 50 µm which are successively spread in layers on top of each other. A computer controlled CO2 laser beam scans the surface & selectively binds together the relevant particles to make the SLS model.

During laser exposure, the powder temperature rises above the glass transition point causing the adjacent particles to flow together - this process is called sintering As the powder is solid, it is self-supporting, so unlike the SLA process, supports aren't necessary for SLS models.

When considering using the selective laser sintering process please bear in mind the following :-

The standard accuracy of SLS models is ± 0.2% / ± 0.2mm, but higher accuracy can be achieved.

The minimum wall thickness is 1 mm, but living hinges are possible with SLS models at 0.3 mm.

The selective laser sintering process creates SLS models which typically have a grainy surface with acceptable roughness. For aesthetic & part evaluation models, the stereolithography process is more suitable.